Materials Data on La3AlNiS7 by Materials Project
La3NiAlS7 crystallizes in the hexagonal P6_3 space group. The structure is three-dimensional. La3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of La–S bond distances ranging from 2.89–3.29 Å. Ni2+ is bonded to six equivalent S2- atoms to form face-sharing NiS6 octahedra. There are three shorter (2.47 Å) and three longer (2.48 Å) Ni–S bond lengths. Al3+ is bonded in a tetrahedral geometry to four S2- atoms. There are one shorter (2.22 Å) and three longer (2.25 Å) Al–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to four equivalent La3+ and two equivalent Ni2+ atoms. In the second S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent La3+ and one Al3+ atom. In the third S2- site, S2- is bonded in a distorted tetrahedral geometry to three equivalent La3+ and one Al3+ atom.